Solenoids typically make use of a high magnetic reluctance region to facilitate movement of an armature in response to the application of an electric current. This region can be referred to as an “air gap” because empty space is commonly used as the high magnetic reluctance region. Such an arrangement, however, may lead to certain difficulties in both construction and operation of the solenoid. Certain prior art teachings disclose the air gap may be achieved through a two piece construction of the solenoid with a gap left between the two pieces. Each piece may have a different conformation, meaning that separate, specialized manufacturing processes could be required for each piece. Further, if the two pieces need to be aligned properly to allow for easy movement of the armature through each piece and across the air gap, extra calibration and alignment procedures may be necessary. All of these additional steps generally increase manufacturing complexity, meaning more time and cost may be necessary to produce a single solenoid than if said extra calibration and alignment procedures were eliminated.
There is the fear of decreased manufacturing efficiency and operational lifetimes associated with prior art solenoids. For example, if a solenoid were produced in a two-piece arrangement with a certain degree of allowed deviation from the ideal alignment of the first and second piece, solenoids may be produced outside of this tolerance, and the time and cost necessary to produce said solenoid would have been wasted. Further, since a two-part construction like the one described above may be unlikely to produce ideal alignments on a consistent basis, the average operation lifetimes of the solenoids may decrease, shortened by failures at weak points (such as welding seams) and by general wear and tear (caused by frictional forces of the armature on the solenoid housing after days, months, or years of repeated rubbing due to misaligned solenoid components).
What is desired, therefore, is a method of making a solenoid housing that eliminates the structural and fabrication complexity of the prior art. It is further desired that the method of providing a solenoid housing be finely tunable and precise, so that the product solenoid housing of the method allows for increased spatial efficiency of components in the product solenoid. Additionally, it is desired to produce a solenoid housing with an increased operational lifetime over the prior art.